Data networks contain various network devices, such as switches, for sending and receiving data between two locations. For example, frame relay and Asynchronous Transfer Mode (“ATM”) networks contain interconnected network devices that allow data packets or cells to be channeled over a circuit through the network from a host device to a remote device. For a given network circuit, the data from a host device is delivered to the network through a physical circuit such as a T1 line that links to a switch of the network. The remote device that communicates with the host through the network also has a physical circuit to a switch of the network. A network circuit also includes a logical circuit which includes a variable communication path for data between the switches associated with the host and the remote device.
In large-scale networks, the host and remote end devices of a network circuit may be connected across different local access and transport areas (“LATAs”) which may in turn be connected to one or more Inter-Exchange Carriers (“IEC”) for transporting data between the LATAs. These connections are made through physical trunk circuits utilizing fixed logical connections known as Network-to-Network Interfaces (“NNIs”).
Many business organizations setup private networks which utilize large-scale public data networks (such as frame relay or ATM) for communicating data between multiple sites. These private networks are known as virtual private networks (“VPNs”). Typically, VPNs include dedicated physical connections to a public data network as well as dedicated physical trunk circuits for communicating data securely through the network to multiple sites. The dedicated physical trunk circuits only carry VPN traffic and thus also include dedicated logical connections or NNIs for communicating logical circuit data within the public data network. Periodically, failures may occur to the dedicated trunk circuits or the dedicated NNIs of VPN network circuits, causing lost data. Currently, VPN network circuit failures are handled by dispatching technicians on each end of the VPN network circuit (i.e., in each LATA) in response to a reported failure. The technicians manually access a logical element module to troubleshoot the logical circuit portion of the VPN network circuit. A logical element module communicates with the switches in the data network and provides the technician with the status of the logical connections which make up the logical circuit. Once the technician determines the status of a logical connection at one end of a logical circuit (e.g., the host end), the technician then must access a network database to determine the location of the other end of the logical circuit so that its status may also be ascertained. If the technician determines the logical circuit is operating properly, the technician then accesses a physical element module to troubleshoot the physical circuit portion of the VPN network circuit to determine the cause of the failure and then repair it.
Current methods of determining VPN network circuit failures, however, suffer from several drawbacks. One drawback is that troubleshooting logical and physical circuits is time consuming and results in dropped data packets or cells until the failure is isolated and repaired. Furthermore troubleshooting the physical circuit often requires taking the VPN network circuit out of service to perform testing, thus increasing the downtime and loss of data in the logical circuit. Moreover, if the failure cannot be isolated by the technicians in a LATA or the failure is located at the interface to the IEC, cooperative testing with the IEC must also be coordinated to isolate the failure leading to a further increase in downtime and loss of data in the VPN network circuit.
It is with respect to these considerations and others that the present invention has been made.